I've been a member for 11 years now and in spite of the membership fee increasing steadily from sub $200 to about $300 this year, I have no major qualms that I have not been responsible for myself (a couple of years I have been too busy to use it properly.)

The simple fact is that it's not a secret society allowing you to show your card and be escorted to your penthouse suite, it's a rewards club with a range of benefits that you have to actively PLAN to use, not react when the end of the renewal month comes around again (and believe me I know about that too!)

On a few occasions I have had to book a complimentary night at the last minute and settle for a property that I would not otherwise stay at but still, is it that much of an imposition?

Points of advice:
1/ Plan your free night MONTHS in advance so that you get the few allocated rooms they make available in the highly popular and therefore low vacancy sites instead of somebody else (let's face it frequent flyer programs are no different in this)
2/ Watch out for the special offers in the publications as these will help you save additional money if you are travelling for specific reasons.
3/ Treat yourself to the occasional weekend or even night away close to home; it's great for your relationships (especially once the rug rats come along) and gives you an extra chance to get some more value out of it by booking a decent spa room in a nice location.
4/ Take advantage of the dining discounts most of all. Just make sure you use it at least a half a dozen times on top of your free night to break even or better.

In short, it's up to you to make the most of it. Accor know that a significant number of people will sit on their bums and not use it actively so the financial proposition for them is acceptable. Meanwhile from those of us who actually use the program for what it really offers, thank you for subsidising me.